# 1.4 Measures of Dispersion for Sample Data Flashcards

What does sample variance use as a point of reference?

The sample mean

By definition, the sample variance is ______________.

non-negative

What is the unit of sample variance?

Expressed in squared units

What is the unit of the standard deviation?

Expressed in the same unit as the sample mean and the random variable

What does the coefficient of variation allow?

To compare samples of data collected for two random variables expressed in different units or samples of data with very different means

What is the unit of the coefficient of variation?

Unitless

Which measure of dispersion is expressed in squared units?

Sample variance

Which measure of dispersion is expressed in the same unit as the random variable?

Standard deviation

Which measure of dispersion is unitless?

Coefficient of variation

What is the equation for sample variance?

What is the equation for standard deviation?

What is the equation for the coefficient of variation?